Conceptualizing and investigating the contextual variability of stuttering: The speech and monitoring interaction (SAMI) framework

Uniqueness Point Effects during Speech Planning in Adults Who Do and Do Not Stutter

“…The outcomes of the present study are consistent with theoretical models that propose that the preverbal monitor in persons who stutter may be hypervigilant (SAMI [30], VRT [31], VCH [32]). That is, if AWS apply an excessively high threshold for phonemic accuracy prior to motor execution, this may slow the detection of the critical uniqueness point phoneme.…”

“…Based on theoretical models that suggest atypical speech monitoring abilities in persons who stutter may contribute to moments of stuttering [30-32], we predicted AWS would not exhibit perception-specific uniqueness point effects exhibited by AWNS when monitoring inner speech [33]. This prediction was supported by significantly faster detection of phonemes that followed an EUP (but not LUP) for AWNS, but no phoneme monitoring latency differences for AWS irrespective of uniqueness point.…”

“…As suggested by Levelt et al [29], both efficient monitoring of preverbal speech and efficient encoding are necessary to maintain fluent, accurate speech production. At least 3 contemporary theories of stuttering implicate atypical preverbal monitoring as an area of compromise in persons who stutter [30-32]. If this is the case, differences attributed to phonological encoding in AWS observed in previous studies, and by extension differences in everyday speech production, may have been confounded by atypical self-monitoring abilities.…”

“…The VRT [31], VCH ([32]; however see Howell [11] and Bernstein Ratner and Wijnen [65] for further discussion), and to a lesser extent SAMI [30] suggest that atypical monitoring in persons who stutter likely originate during childhood due to latent linguistic weaknesses or unique temperamental factors near onset. The present study was restricted to adults and not designed to address whether the differences are present in children who stutter.…”

“…The Variable Release Threshold (VRT) hypothesis proposed by Brocklehurst et al [31] modified Howell’s [3] EXPLAN model to suggest that during moments of stuttered speech, the threshold of acceptable phonemic quality to release an intended speech plan is elevated to excessive levels to accommodate real (or anticipated) imperfections, thereby delaying or halting preparation of speech plans and subsequent execution. Arenas’s [30] Speech and Monitoring Interaction (SAMI) framework expands the notion of excessive or hypervigilant monitoring proposed by the VCH and VRT, but acknowledges that latent difficulties during speech formulation may also be present in persons who stutter. The SAMI model proposes that increased contextual demands may aggravate a vulnerable preverbal monitor in individuals who stutter and, as a result, trigger compensatory cognitive processes (e.g., increased attention, motor inhibition) in response to potential difficulties formulating speech.…”